Revelations last week that Google Inc, Twitter and other popular Internet companies have been taking liberties with customer data have prompted criticism from privacy advocates and lawmakers, along with apologies from the companies.

They are the latest in a long line of missteps by large Internet companies that have faced little punishment for pushing privacy boundaries, which are already more expansive than most consumers understand.

Despite all the chatter about online privacy and the regular introductions of proposed data protection laws in Congress, Silicon Valley is in the midst of a veritable arms race of personal data collection that is intensifying.